Typewriting machine



J1me 1939- R. G. THOMPSON TYPEWRITING MACHINE Filed Feb. 20. 1937 5Sheets-Sheet 1 INVENTOR RUSSELL 6. THOMPSON 5% ATTORN EY June 27, 1939.

9 wmunm :uml m llllllll. llll R. G. THOMPSON 2,163,968

TYPEWRITING MACHINE 3 Sheets-Sheet 2 Filed Feb. 20, 1957 INVENTORRUSSELL 6. THOMPSON BY I? ATTORNEY J1me 1939- R. G. THOMPSON TYPEWRITINGMACHINE Filed Feb. 20, 1937 3 Sheets-Sheet 5 F=====EEEL=EE INVENTORRUSSELL G. THOMPSON ATTORNEY Patented June 27, 1939 UNITED STATES PATENTOFFICE signor to Underwood Elliott Fisher Company,

New York, N. Y., a

corporation of Delaware Application February 20, 1931, Serial No.126,904

7 Claims.

This invention relates to typewriting machines and with regard tocertain more specific features thereof to the means for causing arelative shift of parts of the machine to obtain upper and lower casetyping positions. Some of the broad principles of the invention areapplicable to either manual or power-driven operations although in thepreferred embodiment of those principles shown in the accompanyingdrawings and described hereinafter they are incorporated in a machine ofthe power-driven class.

One of the objects of the invention is to provide simple, rugged andrelatively inexpensive means for positively shifting the carriage or iiibasket from one case position to the other in a quiet manner. Suchquietness of operation is a consequence as well of a power actuation asof one in which the touch ofthe operator effects the movements.

Another object of the invention lies in the provision of a simple devicefor accurately and firmly positioning the carriage or basket in eithercase position thereby insuring absolute alignment of the successivelytyped characters whether 25 of lower or upper case or a. combination ofboth.

It is a further object of the invention to increase the speed ofoperation of a power-driven case-shifting device and obtain the shift toupper case by a selection and slight depression of a key 0 and the shiftback to lowercase by the release of the key, it being optional that thecarriage be immediately restored from upper to lower case position orlocked in upper case by a case-shift lock-down key which holds thecarriage in position for the typing of a succession of upper casecharacters.

In the preferred form of the invention shown in the drawings andhereinafter to be described, it consist of a mechanism comprising a linkand lever assembly with spaced controlling stops by which the part to beshifted to obtain a different case position is moved from one positionto the other and a toggle straightened at the extreme of movement, andmeans whereby this toggle may 4,5 be broken and the part shifted to itsother extreme and another toggle straightened to securely hold theshiftable part in its other extreme position. In connection with thismechanism a continuously rotated power drive element is em- 5 ployed,preferably, and key-operated mechanism causes a transient engagement ofan actuator with the power-driven element to effect the oper ation ofthe'link and lever mechanism. As a feature of the key operated mechanismthe ac- 5s tuator is caused to move in one direction by the depressionof a key lever and in the opposite :lirection by the return movement ofthe same key ever.

In the accompanying drawings:

Fig. 1 is a view in side elevation, with parts of the side frame brokenaway to show more clearly the interior construction, of a. typewriterembodying the improved case-shift device. In this figure the part to beshifted, which, in formof the invention shown, is the carriage, is inlower case position with the power-drive element rotating freely.

Fig. 2 is a view of the same parts shown in Fig. 1 but with thecase-shift key lever depressed thereby connecting the actuator with thepowerdrive element, and the shift mechanism is shown in transit fromlower case to upper case posit on.

Fig. 3 is a view similar to Fig. 1 showing the shifted part in fullupper case position and further showing the lock-down key actuated toretain the shifted part in upper case position.

Fig. 4 is a view similar to the other figures but showing the case shiftlever released from its latched position and returned by its spring, andshowing the engagement of the actuating devices for restoring the shifted part to the lower case position of Fig, 1. The link and levermechanism is shown in an intermediate position indicating that theshiftable part is in transit from its upper case postion to its lowercase position.

Referring now more particularly to the drawings and to Fig. 1 thereof, atypewriter frame is indicated at including a backbone 2i extending fromone side wall 22 of the frame to the other, a throw -off cross bar 23and an anchor cross bar 24 both'of which extend between the side wallsof the frame. The frame further includes a cross member 25 spacedrearwardiy of the backbone for supporting and guiding certain parts ofthe actuator mechanism which will be described later in detail. Theframe further includes a back plate 26 which rises nearly to the top ofthe machine to resist pressures on a carriage having opposite end framepieces one of which is indicated at 21 and a connecting bar or rail 28unites the end frame pieces. Lugs 30 and 3| extend a short distanceinwardly from each of the opposite side walls of the carriage frame andhave secured thereto the lower ends of spring metal strips 32 and 33,the upper ends of which are secured to a cross memher or center tie 34which isprovided in a conventional manner with spaced lugs 35 havingadjustable pivot screws 36 between which is mounted a balancing frame 31having a rearwardly extending arm 38 to which is pivoted a supportingtrack 48 carrying anti-friction rollers 4| on opposite sides forslidably engaging the carriage frame bar 28. The cross member or centertie 34 has a rearwardly extending central web 42 to which is connected atabulator casing, not shown. The center tie also has a rearwardly andupwardly directed arm 43 in a pressure resisting line with the printingpoint of the machine, and this arm carries an angle plate 44 a frontface 45 of which is contacted by a carriage rail 46 extending from oneend frame of the carriage to the other. Suitable means are provided forloosely tying this carriage rail to the angle member 44 in such fashionthat the carriage rail may move freely past theangle plate in the letterspacing or return directions of movement of the carriage and this devicealso permits up and down movement of the carriage by operation of thebalancing frame, all of which is clearly described in detail in aco-pending application of mine Serial No. 126,902, filed February 20,1937.

Pivotally connected to a. forward extension 58 of the balancing frame isa long downwardly extending link 5| the lower end of which is pivotallyconnected by ashort link 52 with the end 53 of a long arm 54 of a bellcrank lever 55 which is pivoted to one of the side walls of the frame at56. The end 58 of the long arm of the lever is in the form of alaterally extending stud 51 which is adapted to move from an adjustablelimiting stop 58 to an adjustable limiting stop 68 both of which areconstituted by lugs extending from the side of the frame and throughwhich screws 6| are threaded each screw having an enlarged wrench-facedhead 62 in which is embedded or otherwise secured a cushion disk 63 ofrubber, fibre,'leather or other suitable material.

At the point of pivotal connection between the long link 5| and theshort link 52 one end 64 of another short link 65 is pivotallyconnected. The other end 66 of this short link is pivotally connected toan arm 61 of a bell crank lever 68 held to the side wall of the frame bya screw 18. This bell crank is angularly adjustable by a screw H havingan eccentric shank portion 12 the screw passing through an upwardlyextending arm 13 of the bell crank lever and engaging with the side wallof the frame. By this means the point of pivotal connection between theshort link 65 and the arm 61 of bell crank lever 68 is variable todifferent set positions.

The movements of the link and lever mechanism just described are clearlyshown in the various figures of the drawings. From the lower caseposition indicated in Fig. l of the drawings with the stud 51 againstthe stop 58 and a toggle consisting of the long link 5| and the shortlink 65 straightened as indicated by the line ILL-LC, the carriage orpart to be shifted is effectively held in lower case position. Initialmovement of the bell crank lever 85 breaks the toggle LC-LC and movesthe stud 51 away from the stop 58 as indicated in Fig. 2 of thedrawings. Continued movement of the lever 55 in this directioneventually seats the stud 51 against the stop 68 as shown in Fig. 3 ofthe drawings, and this creates another straightened toggle indicated bythe line UC-UC at which time the short link 65 having been rocked aroundits pivot point has pulled down the long link 5i and rocked thebalancing frame into the upper case position. A supplemental adjustablestop consisting of a screw 16 threaded through a lug TI on the balancingframe has an end which seats upon a stop 88 on the center 2,1es,oes

tie 34. The carriage may be maintained in this upper case position bymeans which will be hereinafter described. To return the carriage tolower case position the bell crank lever is rocked in the oppositedirection primarily breaking the toggle UC-UC as indicated in Fig. 401the drawings and the parts are returned to their normal relationship asshown in Fig. l of the drawings.

The movement of the bell crank lever 55 in both directions is effectedby a main actuator 8| which is power-driven in opposite directions. Thisactuator is pivotally connected to a short arm 82 of the bell cranklever and carries two swingable actuator bars 88 and 84 which arepivoted at 85 and 86 respectively on the main actuator 8| and depend onopposite sides front and rear of the power-drive member. These actuatorbars carry pivoted pawls 81 and 88 having teeth adapted to engage withteeth on a continuously rotating drive member l5 driven by an electricmotor, not shown. When the pawl 81 is engaged with the drive member asby swinging the actuator bar 88 rearwardly around its pivot the actuatorbar is carried downwardly after first slightly pivoting the pawl toinsure a full engagement of the teeth of that pawl with the teeth on thepower-drive member I5. A tall 88 on the pawl fulcrums on the edge of aplate 41 secured to the backbone 2i and further rotative movement of thedriving member is translated into a downward movement of an actuator baruntil such time as a cam face 48 on the bar 83 engages a throw-ofl screw48 on the cross member 28. This downward movement carries down the mainactuator member 8i which is guided in its downward movement by means ofa slot 14 within which is a pin 18 suitably fixed in relation to thebackbone and frame of the machine. Downward movement of the mainactuator rocks the bell crank lever 55 to move the carriage to the uppercase position shown in Fig. 3 of the drawings. The downward movementjust described also carries down the rear actuator bar 84 positioningthe pivoted pawl 88 where it may be engaged by the power-drive memberwhen the rear actuator bar is swung forwardly, and when it is so swungand engaged the rear actuator bar is moved upwardly carrying with it themain actuator 8| and rocking the bell crank lever 55 in the reverseposition to restore the carriage to a toggle locked position in lowercase.

The mechanism will now be described by which the swinging movements aregiven to the actuator bars and their pawls for causing a powerengagement to eflect both directions of movement. A caseshift lever 88is pivoted in a comb slot 8i running from front to rear through theupper portion of the backbone 2|. The pivot point for the case-shiftlever is indicated at 82 in the form of a pin passed through thebackbone. The lever has a forwardly extending arm 83 which makes a turndownwardly at 84, then forwardly and obliquely downward and forward asindicated at 85. The extreme forward end of the lever has a stem 88 anda key 81. The lever is also provided with a downwardly extending arm 88at the end of which a coil spring I88 has one end Ill connected and theother end I 82 of this coil spring is connected to an anchor plate I88which is adjustably secured to the under side of the cross bar 24. Thisdownwardly extending arm 88 of the lever has a rearwardly and upwardlyextending portion I84 which carries a pivoted dog I 85 having arearwardly projecting nose I 06 adapted to move into engagement with thefront edge of the swingable actuator bar 83.

I This dog has a loose pivot connection I01 with the lever and has aspring I08 connecting an upturned forward end IIO of the dog with a lugIII on the rearwardly and upwardly extending arm I04 of the lever. Thislever arm also has a connected rearward extension II2 which proceedsfirst upwardly and then rearwardly through a comb slot H3 in thebackbone and carries a pivoted dog II4. This dog-carrying part ishorizontally slotted at I I5 (see Figs. 2 and 4) in a fore-and-aftdirection to embrace the pin 19 of the backbone for support. It isfurther supported by the top of the cross bar 25 of the frame.

An upper stop and guide I20 for the case-shift key lever is provided bya channel member I 2I secured in fixed relationwith the frame and oneside I22 of which extends downwardly and is vertically slotted asindicated at I23 to receive and guide the lever. The spring I00 attachedto the depending arm 08 of the key lever holds the lever normallyagainst a strip I24 of sound absorbing material contained in the channelmember. Another channel member I25 is secured to the frame below theforwardly extending arm of the lever and is provided with a soundabsorbing strip I26 the upper edge of which is spaced from strip I24 topermit a limited amount of movement of the lever. As the key 91 isdepressed the lever contacts the lower stop and in its movement from theupper to the lower stop it moves the rearwardly extending arm I04carrying the dog I05 until the end of the dog picks up the swin ingactuator bar 83 and engages the teeth of pawl 81 with the teeth of thedriv ng member. This movement of the, lever also rearwardly shifts theextension bar I I2 carrying with it the rear do II4 which allows for thepassage of a lug I21 on the rear actuator bar as the entire actuatormechanism is moved downwardly by the described engagement with the powerdriver. As the throw-off screw 49 becomes effective to disengage theforward pawl from the driving member the stud 51 at the end of the longarm of the bell crank lever abuts the fixed stop 60 and the upper casetoggle is straightened as shown in Fig. 3. This position of the bellcrank lever will be maintained by the toggle action as long as the keylever is held depressed either by holding a finger on the key 91 or byoperation of a caseshift lever lock-down key I30. This key is piv-' otedon the case-shift lever at I3I and has a depending hook portion I32normally held out of engagement with a latch plate I33 by a spring I34.One end of the spring is connected to the hook portion of the lockingkey and its other end is connected to an arm I35 extending downwardly atthe forward end of the case shift lever. The latch plate I33 is in theform of an angle member which is secured by screws I 36 to the top ofthe anchor bar 24. When pressure is applied to the lock-down key thehook is swung into engagement with the angle plate and slight relief ofthe pressure latches the parts in position. To unlatch the lever the key01 is slightly depressed allowing the spring I34 to return the lock-downkey until a lug I3'I abuts a lower edge of the lever. Whether the leveris held down by pressure of the operator's finger on the key 91 orlocked down by the lock-down key the actuator mechanism is held in itsdown and thrown-off position by means of the straightened toggle UC-UCand stop 80. In this position the lug I21 on the rear actuator isdirectly opposite the forward end of dog II4 so that when the key leveris released for movement under the action of its return spring therearwardly extended bar II2 carrying the rear dog is moved forwardly andthe dog picks up the rear actuator bar and swings it forwardly to engageits pawl with the teeth of the driving member whereupon the entireactuator device is thrown upwardly until the pawl is thrown out ofengagement by a cam face I38 on the lower part of the rear actuator barengaging with'a rear throw-off screw head I40 on the cross member 23.Thus return movement of the caseshift lever from its depressed positioncauses operation of the actuatordevice upwardly to cause reversemovement of the bell crank lever to break the straightened upper casetoggle and straighten a toggle consisting of the long link BI and theshort link 68 and bring the stud 51 against the opposite stop member 58.Tension on the return spring I00 may be varied by shifting the anchorplate I03 forward or rearward on the cross bar 24 and securing it indifferent adjusted positions.

'As the actuator mechanism moves downwardly the forward actuator bar 88when thrown off presents a shoulder I under the nose I00 of dog I05 andas the mechanism returns the dog ls pivoted until the shoulder passeswhereupon the dog is returned to active position by the spring I08. Thepawls 81 and 88 are held spaced from each other by a projection I42 onthe rear actuator bar so that as one pawl is engaged with the drivemember the other pawl must be free therefrom. As the mechanism returnsupwardly the rear dog I I4 pivots to allow the lug I21 to pass whereuponspring means similar to that of the forward dog returns the dog toactive position.

A conventional roller platen is indicated at I43 and is suitablyjournaled in the carriage end frames for movement with the carriage toits upper and lower case positions. .Type actions, preferably of thepower-driven key-selected character, are employed for mdvement towardand from the roller platen but are not shown in the drawings as theyform no part of the present invention.

What is claimed'is:

1. In a power-driven typewriter, a frame, a rotary driving member withteeth, transiently engageable means on opposite sides of the drivingmember for alternative engagement therewith, an actuator carrying saidtransiently engageable means, a lever pivoted on said frame having onearm connected to move with said actuator and another arm having a shortlink pivoted at its end, a part to be shifted from one to another caseposition, a link extending from said part to a connection with saidshort link, another short link extending from the last said connectionto a point of support by said frame, stops for limiting the movements ofsaid lever and links in two alternative straightened toggle positionsand a case shift key lever mounted for operation of said transientlyengageable means, adapted upon movement in one direction to causeengagement of said means on one side of the driving member and uponmovement in the opposite direction to cause engagement of the said meanson the opposite side of said driving member.

2. In a power-driven typewriter, a frame, a rotary driving memberthereon having teeth,-an actuator member, two swingable pawl carriers onsaid actuator member adapted to swing on opposite sides of said drivingmember and each having a pawl adapted to move into and out of engagementwith the driving member, a part to 'be shifted to upper and lower casepositions, connections between said part and said actuator membercomprising a lever and links, stops limiting the range of movement ofsaid connections, a key, and means actuatable by said key for movingsaid swingable means to cause one or the other of said pawls to engagethe teeth of the driving member dependent on the direction of movementof the key and thereby shift the actuator in one direction or the other.i

3. In a power driven typewriter, a frame, a part to be shiftedrelatively to said frame, a rotary driving member, an actuator havingswingable bars adapted for alternative engagement with the drivingmember respectively on opposite sides thereof, a pair of toggles adaptedto be alternatively straightened to raise or lower the part to beshifted, a bell crank lever one arm of which is pivotally united withthe actuator and the other arm of which constitutes a part of one ofsaid toggles and has a stop, and spaced stops on the frame for limitingthe range of movement of said lever.

4. In a power driven typewriter, a frame, a rotary driving member, anactuator having two members for directly engaging the driving memberalternatively and respectively on opposite sides of the driving member,a pivoted lever one arm of which is connected to the actuator and theother arm of which has a stop, a link connected to said other arm, asecond link extending from the end of the first said link to a framepivot, a part to be shifted, a long link between the union of the firstand second links and the part to be shifted, and spaced stops limitingthe range of movement of the stop on the pivoted lever arm.

5. In a power driven typewriter, a frame, a part to be shiftedrelatively thereto, a toothed shaft adapted for continuous rotation onsaid frame, an actuator, two toggles between the part to be shifted andthe actuator adapted to be alternatively straightened to obtain upperand lower case positions of the part to be shifted, and stops todetermine the straightened positions of the toggles, said actuatorcomprising a main body having two swingable bars thereon each having apivoted pawl for engaging respectively at opposite sides of the toothedshaft with the teeth of said shaft.

6. In a power driven typewriter, a frame, a part to be shiftedrelatively thereto, a toothed shaft adapted for continuous rotation onsaid frame, an actuator, two toggles between the part to be shifted andthe actuator, adapted to be alternatively straightened to obtain upperand lower case positions of the part to be shifted,'stops to determinethe straightened positions of the toggles, said actuator comprising amain body having two swingable bars thereon,'each having a pivoted pawlfor engaging respectively at opposite sides of the toothed shaft withthe teeth of said shaft, and a key lever having two dogs articulatedtherewith in such manner that movement of the key in one directionoperates one of the dogs to engage one of the pawls with the teeth ofthe shaft, and return of the key causes operation of the other dog tocause engagement of the other pawl with the teeth of said shaft.

7. An electric-power actuated case-shifting mechanism comprising a partto be shifted, a rotary driving member, an actuator for said part to beshifted having members adapted for alternative engagement with thedriving member respectively on opposite sides thereof, a pair of togglesadapted to be alternatively straightened to raise or lower the part tobe shifted, a lever having one arm pivotally united with the actuatorand another arm constituting a part of one of said toggles and providinga stop, and spaced stops for limiting the range of movement of saidlever.

RUSSELL G. THOMPSON.

